Insulation lining for conduits



Feb. 28, 1950 A. L. BAKER INSULATION LINING FOR CONDUITS 2 Sheets-Sheet 2 Original Filed May 5, 1940 lilllllllllllllnllllllllllll|1 l Ii um INVENTOR. 4455er L .E4/new BY Ressued Feb. 28, 1950 Re.

UNITED STATES PATENT OFF l CE f INSULATION LINING FOR..CONDUI'ISk Albert; L. Baker, Summit, N. J., assignor to The M. W. Kellogg Company; New York, N; Y., a corporation of Delaware Original No. 2,369,204, dated February 13, 1945,

Serial No. 440,922, April 29, 1942, which is, a division of Serial No. 333,093, May 3, 1940. Application for reissue'January'Zfi, 1946, Serial No.

10 Claims.-

rIlhis invention relates in general to conduits, vessels and `the like, through which fluids, are conducted or in' which fluids are processedk and in particular to novel apparatus for controlling the transfer of heat from the fluidl within the (Cl. 13S-6.4)

Matter enclosed in heavy brackets, vIappears in the original patent but forms lno part ofthis reissue specification; matter printed in italics indicates the additions made by" reissue 2. losses-are .substantially reducedy andi minimized. I haveI 'further found thatithe` arrangements; em.- ployed.v for effecting the heat. transfer control, whenfusedin. conduits or vessels handling either condensable or: non-condensableV materials, also.

conduit or vesselto the vatmosphere or other ex- 5 result in a substantial reduction of; the: heat ternal medium. This application is a division of losses.

application Serial No; 333,093, filed` May 3, 1940,- Itisa primary Aobject of.vv this: invention` to pronow abandoned. vide a; novel insulationliner. adapted to line the It is now quite usual in many arts, such as inside surfacesof theiwalls'ofconduitsgor ves.- the power plant, chemical, petroleum refining; sels, which is of. cheap. andi simple construction, and similar arts, tov provide conduits and vessels maybe easilyJ and. cheaply appliedA and makes for handling materials in the gas, or vapor; full useof the insulation..value ofjthe insulating, phase at extremely high temperaturesv and Agenmaterial employed. erally also under [the] extreme pressures. lt. is also .a primary object. of the' invention Temperatures of 1000 F., and more, and presfto provide. novel insulation liner adapted to sures o1" 1000-lbs. per squarench, and more, are bei positioned against` the vinside surfaces of the not uncommon. The materials handled, vfurfwalls: of corlcluitsory vessels,.which includesl an thermore, are often of a corrosivenature. inner metal: wall, that' may be vof non-corrosive Thefabricators of the conduits and vessels f or metal; in contact with. theY bulk of: the materials this class of service have found that carbon handled-in the conduit, orf'vessel, the'metalwall steel', primarily because of, its: low creep-strength being: such. that; it. allows: pressure equalization and inferior corrosion resistance at the operatacross the. full. crossz-sectionfof the conduit, or ing temperatures, is not. the best n'laterial` for vessel,includingt the portion thereof occupied by the purpose and have turned; to alloys of superior 2.5 the lining, .and relative movement between the high temperature creep-strength and corrosion components of thelining so that; in operation the resistance. These alloys aside from'y the special lining components are under. nostress'. due either properties, just mentioned, are generally not as tov thermal; expansion or pressure; the lining, desirable as carbon steel astheyt aremuch. more furthermore, beingr such thatv the: temperature expensive, are morel difficult toy fabricate, require of the metal of the conduit, or Vessel, walls.. is expensiveV heat. treatment. to bring out their reduced materially below that. ofvr thek material special propertiesV andaremore difficult to mainhandled; whereby when media atv high` temperatain and repair. ture are handled the expansion and thermal Because of the extreme service .temperatures stressesinfthe conduit, or'vessel,'wallsare-mateit is usual. lto insulate conduits and vessels of rially reducedl andthe vessels, or conduits, may thistype by covering their outside, surfaces with be safely fabricatedy fromy ordinary materials and suitable insulating materials. The cost of inf designed forf-operationiwithin well` known limits sulating in this manner is vrelatively high. of temperature and pressure'.

I have found, when handlingu materials that Itis also animportant objectfof this invention .are made up of condensable constituents in the 40 -to provide a novelY insulation liner adapted. to gasll or vapor phase, or include both con*- 'f belpositioned against the inside surfaces of. the densable and non-con'densable constituents.` in walls of conduits', or vessels, which is madek up the gasL] or vaporL]` phase, that by the vproper of `a plurality of! connected sections, eachaof the control of the transfer of heat from the high sections, however, being capable of( limited in'- temperature material within the conduit, or-vesdepen-dent movement, each section including. an sel, to the metal walls', the metalV of the Walls inner and' arrv outer'jac'ket between which ispo; can easily be kept within the temperatureljs] sitioned: the. insulating material, each of the range wherein carbon steel has satisfactory jackets havingl at'. their ends corrugations, or characteristics such as creep-strength so that by equivalent stiiening elements, which serveA to employing thismode'of heat transfer control the 50 stiffen the jackets, act asr stops for limiting the special properties of the costly alloysI are not movement of the sections and serve to: hold? the required and the conduits and vessels canV saiely insulating material in position; thev jackets bebe made of carbon steel. I have also found that, ing provided withpassageways thereinxforv pres.- with the materials above mentioned, by vthe surey equalization..

proper control oiA thek heat transfer the heat 5.5 The-further-objects end advantages of theinx- 3 Vention will be readily appreciated from a consideration of the following detailed description of the invention taken with the accompanying drawings, in which,

Fig. 1 is a longitudinal section of a pipe having applied thereto the lining of the invention,

Fig. 2 is a fragmentary sectional view showing the manner in which adjacent sections of the lining are joined,

Figs. 3 and 4 are fragmentary sectional views showing alternative ways of closing the flange ends of the lining sections, and

Fig. 5 is a longitudinal sectional View of a lined portion of a pipe that includes a connector.

The novel apparatus of the invention is of general application and may be applied to vessels of any 4,sort that are used for any purpose. Thus, the novel apparatus may be used in handling liquids, solids, gases, or vapors, or mixtures thereof. When the material handled is in the gas, or vapor, phase it may be all condensable, or it may be all non-condensable, or it may include both condensable and non-condensable constitutents.

While the invention is applicable to vessels and conduits in general, it will be disclosed in connection with a. pipe.

Thus, in Fig. 1 is shown a pipe I0 that includes a wall II with flanges I2 at its ends.l Pipe I0 may be of any suitable material but usually carbon steel Will be satisfactory. When the materials handled are sufciently corrosive the inside surface of pipe III may be defined by a suitable corrosion resistant material such as chrome steel alloy, pure nickel, etc.

Within pipe I is an insulating liner I4. Liner `I4 is made up of a plurality of sections each of which includes a pair of metal jackets I5 and I6 separated by packed fibrous insulating material I1 and I8. Jackets I5 and I6 may be made of any preferred metal suited for the intended service thus, both jackets may be of carbon steel or both of alloy steel of special property. In high temperature service it is at present preferred to make outer jacket I5 of light gage carbon steel and inner jacket I6 of a light gage corrosion resistant alloy such as 14% chrome steel. The thickness of jackets I5 and I6 has been exaggerated in Figs. 1 and 5 so that the construction may be more clearly shown.

Jackets I5 and I6 are formed from sheets that are bent to tube form. The abutting edges of the bent sheets form seams 30, shown in Figs. 1 and 5, which are open to the extent required for maintaining the pressure through the cross-section of pipe II) substantially equal. The abutting edges of the bent sheets may be held together at spaced intervals, as by the tack welds shown. The width of seams 30 has been exaggerated for purposes of illustration. Outer jacket I5 is of such a diameter as to t easily within pipe I0. Inner jacket I6 is of such a diameter that between it and outer jacket I5 may be packed the insulating material II and I8 necessary to secure the desired temperature drop. At present, mineral wool is preferred for insulating material I1 and I8 as this material has the necessary resistance to temperature, is resistant to corrosive media, is of excellent insulating quality and, because of its fibrous character, may be packed to various densities. Of the mineral Wools, lead slag wool, is at present preferred.

At the ends of each of the sections of liner I4 is positioned a plug of insulation I8 of long fiber material; material I1 between plugs IB is preferably in the granular or nodulated form. The

long ber plugs I8 serve to prevent movement of the looser material I'I.

As best shown in Figs. 2, 3 and 4 each of the sections of jackets I5 and I6 [have] has rolled corrugations I8 and 20 provided adjacent each of their ends. At each end of the sections of liner I4 corrugations I8 and 20 are so located that their centers are spaced somewhat along the longitudinal axis of the sections. Corrugations I9 and 2U serve as a means for stiifening the sections of the jackets I5 and I6 as well as a means for holding plugs I8 in position; corrugations 28 also serve as expansion distribution stops as will appear hereinafter. Equivalent stiffening elements may be employed in place of corrugations I9 and 20.

The sections of liner I4 are preferably united by the joint shown in Fig. 2. In effecting this joint a plurality of slotted holes 2l are provided,

preferably equally spaced, around the encircling,`

one of the outer jacket sections I5 of the joint preferably midway between its corrugation I9 and its end. The encircled one of the outer jacket sections I5 is positioned within the encircling one of the outer jacket sections I5 with its end separated from corrugation I9 of said encircling jacket section by a distance at least equal to one half the length of slotted holes 2|. Self-tapping screws 22 are positioned intermediate the ends of slotted holes 2| and driven into said encircled jacket section. By reason of this arrangement the outer jacket sections I5 have a limited independent longitudinal movement, when expanding or contracting, before they are constrained to move as a unit. The encircled one of the inner jacket sections I6 is positioned within the encircling one of inner jacket sections I6 with its corrugation 20 spaced from the end of said encircling jacket section by a distance about equal to the length of slotted holes 2I With this arrangements corrugation 20 of said encircled jacket section and the end of said encircling jacket section act as limit stops for independent movement of their inner jacket sections during expansion of their inner jacket sections I6 and thus prevent warping and other distortion of said inner jacket sections I6.

The sections or liner I4 that terminate at flanges I2 have their ends closed as shown in Figs. 3 or 4. In Fig. 3 the end of inner jacket I6 is bent outwardly to meet the end of outer jacket I5 and united thereto at spaced intervals by tack or spot welds. The end of inner jackets I6 may be bent as shown in the solid lines or it may be bent as shown in the dotted lines, in either case cuts are made, equally spaced around the circumferencev of the end of inner jacket I6, so that the bending may easily be effected. In Fig. 4, a separate piece 23 is used to close the section end. Piece 23 is formed from a tube of appropriate length by bending one end of it[s] outwardly; again, cuts are provided equally spaced around the end of the tube so that the bending may be easily effected. Piece 23 is spot or tack welded at spaced points to outer jacket I5 and may be shaped either as shown in the solid lines or as shown in the dotted lines.

It is to be particularly noted that the construction of liner I4 is such that by reason of the open joints of the elements of the sections, the porous character of the insulating material and the perforated ends of the sections, the space between outer jacket I5 and the wall of pipe III and the vspace between inner jacket I6 'catino and #outer ljaclnei: SI5' arelinhee `=ccinmumcaticn with the L:space Awithin l"inner j'acket fiE Sand `with each other. 4I-Iencethe pressure VAwill always be equal throughout 'the lcrossesection of f the *space within the walls of pipe =I"U. It visalsoto be lparticularly noted -that `except -at the "ver-y ends yof liner 1M- jackets flf5 tvand `"llt are Iunconnected by metal so that throughout diner I4 'the lfu'lliinsulating value -oflthe insulation H and I`8 is l'mfade use of.

In Fig. 5 lis shown the `manner `in *which the sections -of "liner I 4 are formed toline" the lregion of pipe I D that includes `a l:large connector, `such as connector "25. `liner li'vtinthis Aregion -i's -made inthree sections 2E,-2'7,a`nd128.

ESectionZBis made -inthe-'saine manner as -the end Ysections -of "liner "I-"4 above `described and its flange end closed as shown in either Fig. 3 or Fig. '4. The xend of Isection 2B lwithin pipe=iIU Eis shaped to jthe contour ci ithe intersecting 'cylindrical surfaces. This lend Aci section 2li is Lclosed as shown in Fig. 3 except that 5the -outer 'jacket I5 is bent ltorneet Lthe "inner jacket IT. -In this case, as before, the bent end is Vprcrvided with spacedcuts before bending. Section21 isformedv in the 'same way 'as an intermediate section of liner T4, abovedescrbed,'except'or'the end below connector 25. This "endjl above the 'center of pipe "I ll is shaped to tthe vlcontour of 'the 'intersecting 'cylindrical surfaces 'so fasto closely match the abutting-end of'section`26. Below the center line of pipe 'I "the-end 'of 'section '27 is formed to `be in a plane `transverse'to longitudinal axis of 'pipe IU. The'shapedend ofse'ction 2l is closed by bending 'outer jacket IS to inner v'jacket t5 `as stated in yconnection 'with section 26. Section [28] 28 i'sforme'd in the 'same way as the end section 'of lining I4,l above described, and its inside end formed to 'match vthe ends of sections 26 and 21 in the 'manner kdescribed 'in connection `with these sections. Since vrelative movement :between 'sections y26, 27 and "2:8 is not `desirable these sections are preferably tied together by tack, 'or spotwelds.

While 'the lining of a cylindrical bo'dy only has been 'described 'it vshould be obvious that bodies of any shape may be lined :in accordance with this teaching.

Lining I4 is made tohave such an insulating value that it will lprovide a desired temperature drop between the material, within inner jacket I6, i. e., the bulk `of the .material handled, and the insidesuriace ofthe wallsof Ypipe l0. Knowing the operati-ng conditions, the kcharacteristics ofthe material to be handledasw-ellas the characteristics of the materials oi lining I4 and pipe I, it is a simple :matter to calculate from known formulae the thickness of the insulation material, at a preferred densityofLpack,.required with- 'in ylining I4 to give the necessary temperature drop.

While lining I4 is permeable 'to the 'extent above stated, it is not permeable to the extent that there is any substantial iiow of the material handled, -after equilibrium, .from the :region adjacent the inner jacket I6 vtothe region adjacent the walls of pipe l0. Thus, the heat transfer that ltakes place by reason of the material handled between the Walls o'fppe I0 and inner jacket IB takes place to amajor degree through conduction and radiation between quiescent, or at most 4slowly moving molecules of the material handled rather than bymo'vemeiit of the molecules of the material handled.

11. tubu'lar insulating lmlember, saidniemiber including unconnected concentric-,ally 'disposed inner and outer metal jacketsfsaid j ackets `'being spaced from 'each other to provide anannular open -e'nded chamber, said jackets having openings therein for communication with saidan'nular-chambenand porous insulatingmaterial disposed in said chamber-to provide `a h'eat :barrier between said jackets of substantiallyfuniform heat icoro'ductivity said Aporous material 'serving as the' sole means fior maintaining said jackets in their spaced relation, theinsulatingmaterial at the yends oilsaid `chamber being felt-like and movable fas la unit, leach of said jackets being corrugated adjacent their ends, said corrugations :being disposed vin spaced planes transverse to lthe `longitudinal aXis of said member, said c'orrugations serving Ito maintain said ffelt-'like insulatingmaterial Ain position.

2. An insulating member including generally concentric inner and outer .metal jackets spaced fron-reach othertofprovide an open endedannular chamber, porous insulatii'ig material disposed in said annular chamber forming a continuous heat barrier-of substantially-uniform conductivity, the insulating material adjacent the ends of Said jackets being movable as a unit, the remainder of theinsulating material being subdivided yinto individually movable portions, said jackets 'having at yleast one passageway therein between their ends 'providing communication with said chamber for pressure equalization, and means adjacent theends ofeach of s aidjackets vserving to `'stiifen said jackets againstcollapse'and-to maintains'a'id insulation 'movable as a unit Xed in position.

3. In apparatus for handling media at elevated temperatures, a Avessel, an insulation liner positioned 'adjacent the 4inner surface of the vessel Walls,sai"d`\liner comprising a plurality of sections and means connecting adjacent sections for liniited Y'relative movement, each of said sections including spacedinner andouter metal jackets, said jackets Vproviding a continuo-us space between them 'extending for the full length of said liner, porous insulating material yin the space between said jackets, -the insulating material adjacent 'the ends of said jackets being movable as `a. unit,and means fat the endofleach of said jackets engaging the insulating -material thereat to prevent movement thereof, said jackets including atleast one opening therein through Which the heated medium can -pass for equalizing the pressure Within said vessel and the space between vsaid jackets.

4. Iniap'paratus yfor `handling media at elevated temperatures, va vessel, an insulation liner formed oi' -akplurality 'of sections disposed adjacent the inner surface of the vessel walls, each of said sections 'including 'inner and outer metal jackets spaced to provide an uninterrupted annular chamber, porous insulating material filling said annular chamber, the `insulating 'material fadj'acent the ends -of -s'aid jacket being felt-likeian'd movable as a unit, said jackets having corrugations therein adjacent each of their'en'ds extend'- ing Vrinto said chamber to engage 'said felt-like insulating material to restrain it against movement, said jackets having at least one opening therein "through which the heated medium can pass for equalizing the pressure within said vessel and vsaid chamber, the ends of the jackets lof adjacent 'sections Abeing telescoped within 'each other with the felt-like `insulating material 'in abutment, and means connecting the telescoped,

ends of Said outer jackets, said means arranged to provide limited relative movement between the connected outer jackets.

5. A vessel ,for handling media at elevated temperatures and at super-atmospheric pressures, a heat insulating liner disposed against the inner walls of the vessel including a depth of permeable insulation and partition means adapted to confine the medium handled to the central space of the vessel, said partition means being incapable of resisting the effects of large dierences in pressure on the sides thereof, said partition means being provided with one, or more, passageways for restricted flow of the medium handled to equalize the pressure on the sides of such partition means, said one or more, passageways being so restricted in area over the full range of temperatures attained by said partition means to prevent substantial flow of the medium handled into and through the space between said partition means and said inner walls.

6. A vessel for handling media at elevated te-mperatures and at super-atmospheric pressure comprising, an impervious pressure resisting wall, a second wall spaced inwardly from said impervious wall and adapted to confine the medium handled to the central space of the vessel, permeable insulation between said walls, said second wall being incapable of resisting the effects of large differences in pressure on the sides thereof, said second wall having one, or more, restricted passageways therein for sufficient flow of the medium handled to equalize the pressure on sides thereof, said one, or more, restricted passageways maintaining their restricted area over the full range of temperatures attained by said second wall without decrease sufficient to prevent flow of material handled for pressure equalization or increase su'icient to permit substantial flow of the material handled into and through the space between said walls.

7. A vessel for handling media at elevated temperatures and at super-atmospheric pressures, a heat insulating liner positioned against the inner walls of the vessel including a depth of porous insulation and partition means separating the space occupied by said insulation from the central space of the vessel, said partition means being incapable of resisting the eects of large differences in pressure on the sides thereo] and havy ing one, or more, restricted passageways therein for flow of the medium handled to equalize the pressure on :the sides of said partition means, said one, or more, passageways maintaining their area withoutl effective diminution as the temperature of said partition means rises to equilibrium due to contact with the material handled, and means supporting said partition means for substantially unrestrained longitudinal and radial expansion and contraction while maintaining said partition means in a predetermined positional relation relative to the walls of the vessel.

8. A vessel for handling media at elevated temperatures and at super-atmospheric pressures, a heat insulating liner positioned against the inner walls of the vessel including a wall defining member made up of a plurality of separate sections adapted to confine the medium handled to the central space of the vessel and permeable insulation in the space between said wall defining member and the vessel walls, said wall defining member being incapable of resisting the effects vof large differences in pressure on the sides thereof and having one, or more, restricted pase.

sageways therein for flow of the medium handled to equalize the pressure on the sides of said wall defining member, said one, or more, passageways maintaining their eective area over the ltull range of temperatures attained by said wall defining member without decrease sufficient to prevent flow of the material handled for pressure equalization or increase sujicient to permit substantial flow of the material handled into and through the space between said wall defining member and said vessel walls, and means supporting said separate sections for substantially unrestrained longitudinal and radial expansion and contraction while maintaining said wall delining member in a predetermined positional relation relative to the inner walls of the vessel.

9. A vessel for handling media at elevated temperatures and at super-atmospheric pressures, an impervious pressure resisting wall, a second wall spaced inwardly from said impervious wall and adapted to confine the medium` handled to the central space of the vessel, said second wall being made up of a plurality of overlapping sections incapable of resisting the effects of large dilerences in pressure on the sides thereof, the overlapping portions of said sections providing restricted passageways substantially longitudinally disposed relative to said sections for restricted flow of the medium handled therethrough to equalize the pressure on the sides of said sections, said passageways maintaining their area without effective diminution or increase over the full range of temperatures attained by said sections due to contact with the medium handled.

10. A vessel for handling media at elevated temperatures and at sub-atmospheric pressures, an impervious pressure resisting wall, a second wall spaced inwardly from said impervious wall and adapted to confine the medium to the central space 0f the vessel, said second wall being made up of a plurality of overlapping sections incapable of resisting the effects of large differences in pressure on the sides thereof, the overlapping portions of said sections providing restricted passageways disposed substantially longitudinally relative to said sections for restricted flow of the medium handled therethrough to equalize the pressure on the sides of said sections, said passageways maintaining their area without effective diminution or increase over the full range of temperatures attained by said sections due to contact with the medium handled, and means supporting said separate sections for substantially unrestrained longitudinal and radial expansion and contraction while maintaining said second wall in a predetermined positional 'relation relative to said impervious pressure resisting wall.

ALBERT L. BAKER.

REFERENCES CITED The following references are of record in the file of this patent or the original patent:

UNITED STATES PATENTS Number Name Date 1,714,948 Con May 28, 1929 2,013,193 Statfeld Sept. 3, 1935 2,068,180 Horsman June 19, 1937 2,142,542 Wallach Jan. 3, 1939 2,215,532 Richardson Sept. 24, 1940 FOREIGN PATENTS Number Country Date 488,913 Great Britain July 15, 1938 

